Managing Mail Quotas
Every mailbox (with the exception of your master account) has a quota — an allowable maximum size which is established when the mailbox is created (quotas can always be changed later). When an email account hits 80% of its storage quota, email warnings will be generated to alert the mailbox owner. When an account hits 100% of quota, mail will be held on the server’s queue rather than delivered.
After four days at 100% of quota, if the quota issue is not addressed, mail will be returned to sender marked “over quota,” removed from the queue, and discarded by the server. Such mail cannot be retrieved, so it’s important to address quota problems quickly.
Mailboxes can go over quota for many reasons.
1) The quota is simply too small. Most users are comfortable with a quota of 30-50 MBs, though some power users like a quota of 100MBs or more. If you do not have access to the master account on Birdhouse, ask the person who does to increase your quota.
2) The user’s desktop POP client may not be configured to delete older mail from the server. This is critical. Check your mail client’s account options or settings to control this behavior.
3) The user may be using IMAP or Webmail and leaving everything on the server indefinitely. The issue may be solved by simply “emptying the trash” — look for options like “Expunge” or “Purge.” IMAP users should archive mail they want to save permanently in mail folders in their local mail client (in most IMAP applications, when you create a new folder, the default is to create it locally rather than on the server). Also check the webmail or IMAP client’s options for what to do with deleted messages - they should be set to remove from server after a given period of time. Finally, check the size of the “Sent Items” mailbox - these can swell slowly but steadily over time.
4) The user may have enabled the “Spam Box” feature in cPanel, and then forgotten ever to check / empty their spam box. For this reason, we don’t recommend using the Spam Box feature — better to have most spam deleted by the server, and let your mail client handle the rest. Turn Spam Box off in cPanel, and enable spam filtering instead.
5) The user may have received a lot of large attachments recently. These may need to be deleted from the server immediately, or the user may need a larger mail quota.
Contact Birdhouse Support for assistance if necessary.

